Originally Posted by Mike Sams
The desire to win or the desire to fight hard to get the win? Because Nadal has to fight and grind to win. That's his style.
All players have to push themselves incredibly hard trying to be the best they can be and better still. You must have a great DESIRE to push yourself that hard. Once you feel you don't have it anymore (the desire, the thrilling) you are lost, nothing you can do about it.
Some players get to that stage at 30-something, others at 30, other at 25....(it depends on many different factors).